Fifty Plus (50+) - Gearing for Climbing Question

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I'm a terrible climber. Most of it is me, not the bike ("it's the legs, not the bike!"). However, I need to gain just a little more help from my bike then I'm getting ("are you in the lowest gear on that thing?").
I ride a Look 566 with Ultegra gruppo. It's a 50 - 35 compact with (it says on the cassette) CM 5600 12 -25t. On steeper grades (more than 10%), when standing I can just about turn over the cranks, and if I sit - oh, my. My problem is I cannot stand for long, I flood with lactic acid and just die! I need a lower gear!!!
I've done a little reading, and I've discovered that the cyclocross bikes seem to use a 11 - 28t cassette. Lower gear, right? Would that work for me, if I was to change out the cassette on my bike to an 11 - 28t?
Thanks in advance!
You might want to think about an 11-34 rear cassette. This will require a rear derailleur change, but it will give you some nice gearing. The Shimano Deore RD works well and is not expensive. I've set up several bikes this way for friends and family.
This is the way my commuter bike is set up, and I genetrally use it for most rides rather than my "good" road bike. I also run smaller chinrings on it.
http://i783.photobucket.com/albums/yy112/Doug64_photos/Bianchi/TrekDrivetrain-2.jpg
It must climb like a goat with the triple and that 11 - 34! Impressive!
Umm, my Look is my only road bike, and it was rather expensive. Your suggestion is great, but I'm not sure I'd want to go that extreme with it.
198584
B. Carfree
04-19-11, 11:32 PM
Put the 11-28 on and give it a whirl. That lowers your lowest gear by about 12%. If your crank can take a smaller chain ring you can get a little more by going to a 34 or even a 33 tooth small chain ring. Also, have someone knowledgeable look at your climbing technique, particularly when you are in the saddle, to make sure you are involving as many large muscles as you can (are you feeling it in your buttocks?).
I do most of my riding on my touring bike, so I have a triple (48-34-24, 11-28). However, I have never actually used the granny gear when unloaded. Well, I did use it once to tease a friend on a climb when he ran out of gear and was struggling to turn the cranks over.
Put the 11-28 on and give it a whirl. That lowers your lowest gear by about 12%. If your crank can take a smaller chain ring you can get a little more by going to a 34 or even a 33 tooth small chain ring. Also, have someone knowledgeable look at your climbing technique, particularly when you are in the saddle, to make sure you are involving as many large muscles as you can (are you feeling it in your buttocks?).
I do most of my riding on my touring bike, so I have a triple (48-34-24, 11-28). However, I have never actually used the granny gear when unloaded. Well, I did use it once to tease a friend on a climb when he ran out of gear and was struggling to turn the cranks over.
I misspoke in my opener! The chainring IS a 50 -34!
Yes, I feel it "in my butt" when seated, and struggling to turn the cranks over can apply to me (at times) as well. I have had other riders "rescue" me on climbs, they were offering encouragement (less so now - "Sara again - still slow..."). No one has said anything about my technique except to suggest standing straighter, and that I'm stronger than I think. Oooookaaaaayyyy....
Where is Evie Stevens when I need her??
stapfam
04-20-11, 12:41 AM
Thought it must be a 34t. Gearing for hills is down to the rider and their fitness- and bike setup and speed and severity of hills. I have plenty of 10 to 15% hills where I live but most of them are not too long. But I do have to have the gearing right for me to be able to conquer them. I run a compact with 12/27 cassette. That gets me up all the hills but like you I am slow. I take my own pace on all hills and NEVER attack them. May chase other riders near the top if I am near them but that rarely happens. I also use a heart monitor and use that to gauge how much effort to put in. I normally ride on the flat at around 135 to 140 and on hills get to 150. I may reach my max of 160 by the end of the hill if it lips up or I just want to see my max for the day but at no-time do I "Go" for a hill.
On the gearing-I do have one bike set up with a 12/25 cassette and "IF" I use that set of wheels on the steep hills- I know it. That extra 2 teeth on the cassette makes the difference between struggling and surviving.
JimF22003
04-20-11, 02:18 AM
I've used the 11/28 for the last couple of years. I feel no shame any more :)
cyclinfool
04-20-11, 03:51 AM
Sara,
On the bike I use for climbing I have a tripe 54/39/30 and can replace the 12-25 with an 11-28. I don't like the 11-28 for normal road riding because of the gear spacing. So depending on the ride I switch out cassettes. This bike is used for the long climbs, those lasting miles. My other bike is set up just like yours, I can climb with it as well but I can't do the long steep hills.
Other options for you would be to change the chain rings. Although I have not done it, you may be able to have your inner chain ring swapped out for a 30 or 32. You would probably need to a chain drop guard on the bike as well.
Now to what Stapfam said - climbing also depends a lot on your fitness level, both strength and weight. For me I know I don't climb comfortably until my weight is low and I have built up my strength. Since I live in the great North east I have to go through this pain every year as I work off the winter fat. I am currently training for a hill climb race, Only 8.5 miles but up 3500' of vertical. I go out and seek hills, small 1000' climbs at first build up each week until both my strength and mental will is back. So don't try to be a great climber overnight - it takes time. One other thing I have noticed, if you just gear down, you can reach a point were you are actually slower and more uncomfortable on a climb, climbing requires force on the chain and it's hard work - there is just no way around it.
Harris Cyclery makes a custom 30T cassette they call the Century Special.
It works with most road derailleurs.
http://sheldonbrown.com/harris/k7.html#9
Harris Cyclery makes a custom 30T cassette they call the Century Special.
It works with most road derailleurs.
http://sheldonbrown.com/harris/k7.html#9
With most derailleurs, yes, but not with all shifters. The OP rides 10-speed, the cassette you're recommending is 9-speed. Won't work.
With most derailleurs, yes, but not with all shifters. The OP rides 10-speed, the cassette you're recommending is 9-speed. Won't work.
http://www.bikeman.com/BTI-RD2989.html
alanknm
04-20-11, 05:33 AM
I ride with 11-28 and it works fine for me. I seldom use the 28 and I've had people tell me that I should switch to 12-25 but it's useful sometimes for those short nasty steep hills where I ride.
There's no reason why you couldn't go to 11-28. I see that Shimano CS-6700 (Ultegra) has 11-12-13-14-15-17-19-21-24-28 that is supposed to work fine with your existing rear derailleur.
Are you sure it says CM 5600 ? CS-5600 is Shimano 105 (2010). According to the Shimano website, you can use a 105 11-28 (CS-5700) or the Ultegra (CS-6700) cassette.
BluesDawg
04-20-11, 05:57 AM
Sarals, I would first switch to an 11-28 cassette for an easy improvement in gear range. That, along with improving your strength and climbing technique, may be enough to get you up the hills better. Climbing technique is a deep topic and the subject of many threads and articles. Search the forums and Google for more advice than you can digest.
My top tips for climbing are to do it often and to concentrate on spinning circles with your feet to get more power out of your pedaling. It may help to visualize scraping mud off the bottom of your shoes as each foot moves rearward through the bottom of the pedaling circle. When I feel my cadence dropping on a climb, I concentrate on pedaling full circles and will often see my speed start creeping up.
Next step would be a rear derailleur switch to a MTB one (Deore, SLX, XT etc.) and a MTB cassette with a 32 or 34 tooth largest cog.
stapfam
04-20-11, 06:04 AM
With most derailleurs, yes, but not with all shifters. The OP rides 10-speed, the cassette you're recommending is 9-speed. Won't work.
There is an IRD cassette 10 spd that covers this range and before the MTB shimano 10 spd came out- this was the one you had to buy if you wanted to climb a wall with 10 spd. BUT IRD cassettes do not change as crisply as Shimano and for that reason-it is better to buy a better quality cassette.
BikeWNC
04-20-11, 06:42 AM
Even the faster guys here in my town ride a 50/34 compact with an 11/28 cassette. These guys ride sub 6 hour 10K' climbing centuries. Of course the Cat 1 cyclists ride standard doubles but we're not Cat 1s are we? 10% grades are getting pretty steep. Even in my 28 I will be turning the cranks over at a low cadence, perhaps in the low 60s or lower. I have one bike setup with a compact crank and an 11/32 cassette. I use it when I expect steep grades on a longer ride. I'm thinking of replacing that cassette with an 11/34 for the Century ride I'm doing in May that ends with a climb of 3 miles at 12%. At mile 101, facing that climb, there isn't a gear low enough!
Barrettscv
04-20-11, 07:17 AM
I would keep your existing crank-set & brifters, but go to a 12-32 Sram Apex ten speed cassette when riding hilly routes. You will need a new derailleur, like a Shimano Deore SGS and a new chain. This will give you a really huge range and the hills will take less out of you.
The spacing of some the gears is twice the change in cadence of your current cassette. If all your rides are hilly, the 12-32 is all you will need.
See the following thread, I've mixed the Sram Cassette with Ultegra Brifters and derailleur with great results: http://www.bikeforums.net/showthread.php/669790-Sram-Apex-11-32-10-speed-cassette-Shimano-shifters-amp-rear-derailleur-fear-no-hill
I've just put together a custom cassette with a 30 T cog because I want to do some touring in the mountains of New Hampshire. I did not want wider spacing in the higher gears. So it may be you can just change out one cog of your existing cassette to achieve the low gear you need and are otherwise satisfied with the other gears.
I am also mightily influenced by how smooth and effortless the best athletes make their sports appear. My experience is with skiing and tennis. It is a pleasure to just watch good athletes perform. Along this line of thinking, I enjoy watching this video http://www.youtube.com/watch?v=HRFNKhNhhJQ&feature=channel. The man in the video is very fit obviously but he is also very smooth - no wasted energy. My knees are on fire climbing but I'm getting better. Like Bluesdawg suggests, I'm paying attention to the pedal stroke and trying to look like the guy in the video although I'll never be that young again.
I need to gain just a little more help from my bike than I'm getting...
Bikes are our friends. They want to help us (http://youtu.be/FgIL6eHHgZU) climb.
pennstater
04-20-11, 07:50 AM
Try a 105 11-28 cassette. They are relatively inexpensive. Weigh only slightly more than the Ultegra. In my experience 105 shifts and wears just as well as the more expensive Ultegra. You can even install it yourself with some readily available inexpensive tools. See the Park Tools web site for directions. If the 28 is not enough, many people have reported success with larger cassettes like the above mentioned Apex with short cage Ultegra RDs even though it exceeds the published specs. This seems to be a function of RD hanger length and a willingness to accept some chain slack in the small/small combination that you should not be using anyway. Also make sure your chain is long enough for the 28. I had no problem swapping the 11-25 that came stock on my wife's 566 with a 12-27 without changing the chain. Made a huge difference in her hill climbing. I personally don't like the large jumps between cogs when going to a wider range cassette and would make the change to a triple instead of anything over a 28.
Allegheny Jet
04-20-11, 07:58 AM
Bikes are our friends. They want to help us (http://youtu.be/FgIL6eHHgZU) climb.
I call BS! The guy had the tail wind behind him, a walker nearly beat him up the hill and the little girl near the bottom had a birthday sometime during his climbing attempts.:lol:
alcanoe
04-20-11, 08:23 AM
I've always liked lower gearing . When younger, I didn't have time to ride enough to be bike fit and I'm not the athlete most road bikes are geared for.
I've always put a mountain bike crank set on my wife's road bike (22/32/44) with an 11-32 mountain bike cassette. You need to use a mountain bike rear dérailleur. For my cyclocross based road bike I use a TA 22/36/46 crank set (the rings are changeable over a wide range) with a 12-27 road cassette with a mountain bike rear dérailleur. By adding a few links of chain (with SRAM gold links) I can easily switch the cassette out to an 11-32 for the N Georgia mountains. That combination exceeds the rear dérailleur capacity, but it doesn't matter as the 22 ring is not used with the smaller cogs anyhow.
Al
Barrettscv
04-20-11, 10:40 AM
Sarals,
Here is a chart with both your current gearing and one with an 12-32 cassette. An easy way to review this conversion is to think about adding two lower gears, the 34/28 & 34/32. However, you will be losing a intermediate gear combination:the 50/16 which you might miss.
http://i289.photobucket.com/albums/ll210/wildcat-bucket/12-25v12-32.png
SaiKaiTai
04-20-11, 10:44 AM
I read the gears y'all are using and I feel so inadequate. Granted, I'm packing more poundage than I should be but I really have to wonder if asthma has a much broader effect than I realized. On my old Lemond -a 9 speed- I used a 30/30 to get up some of our local climbs. That worked pretty well. I lost that option when I got my Giant, where I have a 30/28 for my lowest gear. I can still get my HR way up there. I just figure the gears you guys talk about will always just be a fantasy to me.... though a little voice in my head keeps saying "Try a compact". I mean, how much difference is there, really, between a 30T and a 34T?
Barrettscv
04-20-11, 10:59 AM
I read the gears y'all are using and I feel so inadequate. Granted, I'm packing more poundage than I should be but I really have to wonder if asthma has a much broader effect than I realized. On my old Lemond -a 9 speed- I used a 30/30 to get up some of our local climbs. That worked pretty well. I lost that option when I got my Giant, where I have a 30/28 for my lowest gear. I can still get my HR way up there. I just figure the gears you guys talk about will always just be a fantasy to me.... though a little voice in my head keeps saying "Try a compact". I mean, how much difference is there, really, between a 30T and a 34T?
I would keep the Triple. Not only will you have extra low gearing, the middle ring is very useful on flat sections.
I ride with 11-28 and it works fine for me. I seldom use the 28 and I've had people tell me that I should switch to 12-25 but it's useful sometimes for those short nasty steep hills where I ride.
There's no reason why you couldn't go to 11-28. I see that Shimano CS-6700 (Ultegra) has 11-12-13-14-15-17-19-21-24-28 that is supposed to work fine with your existing rear derailleur.
Are you sure it says CM 5600 ? CS-5600 is Shimano 105 (2010). According to the Shimano website, you can use a 105 11-28 (CS-5700) or the Ultegra (CS-6700) cassette.
No, I'm not sure. I was looking at it last night in dim light - it said "** 5600 HG Hyperglide Shimano Japan". Perhaps it is "CS". Maybe it is a 105 cassette after all? It won't be until tonight, when I get home from work, that I can look again (drat, I should have brought my bike with me).
Another question - can I change the individual gears, say, swap the 25t for a 28t gear on my cassette (and maybe the gear below it for better spacing)?
Sarals,
The cheapest gearing option is swapping out the rear cluster and getting a larger big cog. Of course, this option comes at the expense of possibly getting into larger gaps between gears. With a 10 speed cluster, gaps are usually not a big problem. A rule of thumb is more than 2 teeth between shifts is not good unless it is that last shift to your biggest cog. Since most riders use the big cog for situations of "I hope it is going to be low enough" a big shift is not such a bad thing on the last cog.
The other solution to getting lower gearing is to go to a triple chain ring system. The small chain ring is not that much smaller on road bikes at 30 teeth. But I understand that one can sneak in a 28 tooth ring and it will work. Combined with a 28 big cog, you have a 27" inch gear which is pretty darn low. But that is an expensive solution requiring either a new bike or new shifters and deraillers on your current ride.
Another option is to go with a cassette that has a really low gear like the 31 people are talking about. That is almost as good as the triple. The shifting probably will have large gaps which is not good. But if you are not riding big hills routinely, you can just swap out the cluster for the "big" days. That option can work well too.
Oddly enough, triple chain rings is an option that many riders eschew in favor of the compact gearing. The weight is about the same. Now I have ridden both systems. I like 2 rings for better shifting. But on a triple, you are not on your small ring unless you are on a honking hill anyway, so shifting is the least of your worries. For long climbs, nothing beats a triple.
Fortunately, here in FL, I can climb the steepest climb in the state in my 39/23 or is it 25? I have not checked in so long.
When I went out of the state to places with mountain climbs, I always used an old bike with a triple.
Try a 105 11-28 cassette. They are relatively inexpensive. Weigh only slightly more than the Ultegra. In my experience 105 shifts and wears just as well as the more expensive Ultegra. You can even install it yourself with some readily available inexpensive tools. See the Park Tools web site for directions. If the 28 is not enough, many people have reported success with larger cassettes like the above mentioned Apex with short cage Ultegra RDs even though it exceeds the published specs. This seems to be a function of RD hanger length and a willingness to accept some chain slack in the small/small combination that you should not be using anyway. Also make sure your chain is long enough for the 28. I had no problem swapping the 11-25 that came stock on my wife's 566 with a 12-27 without changing the chain. Made a huge difference in her hill climbing. I personally don't like the large jumps between cogs when going to a wider range cassette and would make the change to a triple instead of anything over a 28.
Excellent, thank you - you answered my OTHER questions!
I went to bed last night with two responses to my thread, and now - well - I'm reading through them!
Thanks to you ALL!!!
No wonder I enjoy the bike so much, the people are GREAT!!!
By the way, I shot this video climbing one of the hills we have here, Barloy Canyon Road (north side of Laguna Seca raceway, if you know it), last fall. I climb better now, but I'm still S L O W...
http://www.youtube.com/watch?v=5glXf1vH-mc
BikeWNC
04-20-11, 11:50 AM
By the way, I shot this video climbing one of the hills we have here, Barloy Canyon Road (north side of Laguna Seca raceway, if you know it), last fall. I climb better now, but I'm still S L O W...
http://www.youtube.com/watch?v=5glXf1vH-mc
This climb? http://www.strava.com/climbs-by-country/united-states/california/monterey/barloy-canyon-rd-288363
It seems short and not so bad?
This climb? http://www.strava.com/climbs-by-country/united-states/california/monterey/barloy-canyon-rd-288363
It seems short and not so bad?
That's the very one.
It is short, oh, 3 miles, but there are two kicks in it. The first one is about 100 yards long at 13% or more, and the last one is near the top, with a left curve in it, and it's about a quarter mile long. It's 13% or more, too.
I'm a glutton for pain, and I usually climb it at least once a week! I just want some more HELP from the bike!!!! Cat *anything* racer I'm not, and I'm on the 50+ thread because???? - ;~)
BikeWNC
04-20-11, 12:06 PM
For short sections like the ones you noted, sometimes you just have to stand up and gut it out. I could tell that is what you did in the video so really that's what it takes. Sometimes I'll just stay seated and lean over the bars in a low position and try to stay as smooth in the pedal circle as possible. Either way 13% is gonna hurt. The more often you do really steep sections the better you'll get at them. As a side benefit, the 6% stuff will seem a lot easier too.
freighttraininguphill
04-20-11, 12:34 PM
By the way, I shot this video climbing one of the hills we have here, Barloy Canyon Road (north side of Laguna Seca raceway, if you know it), last fall. I climb better now, but I'm still S L O W...
http://www.youtube.com/watch?v=5glXf1vH-mc
I feel your pain. I'm still trying to lose weight, so my climbing sucks. I'm 5' 4" and 155 pounds. That means I'm hauling 30 pounds of useless blubber up every hill. Here's one of my videos from 4-10. This is Ridgeview Drive in El Dorado Hills, CA.
I had just put an 11-34 cassette and 24-tooth small chainring on my Specialized Sirrus hybrid, so I figured what better way to test it out than by climbing a steep hill I've never ridden before. This one had a lot of 13% and a maximum of 17% according to my Garmin. I think I managed to stay in the second to lowest gear though. I've ridden this bike on several other steep climbs since this video and so far I haven't had to use the lowest gear.
http://www.youtube.com/watch?v=5UoYR4Awhfk
http://www.youtube.com/watch?v=5UoYR4Awhfk
fietsbob
04-20-11, 12:35 PM
I have a Campag 'race' triple comes as 50,40,30, the 30 is on a 74 bcd so I fit a 24t.
Don't ride that bike much , I like the Rohloff better, as each gear is in linear sequence.
BikeWNC
04-20-11, 12:49 PM
I feel your pain. I'm still trying to lose weight, so my climbing sucks. I'm 5' 4" and 155 pounds. That means I'm hauling 30 pounds of useless blubber up every hill. Here's one of my videos from 4-10. This is Ridgeview Drive in El Dorado Hills, CA.
I had just put an 11-34 cassette and 24-tooth small chainring on my Specialized Sirrus hybrid, so I figured what better way to test it out than by climbing a steep hill I've never ridden before. This one had a lot of 13% and a maximum of 17% according to my Garmin. I think I managed to stay in the second to lowest gear though. I've ridden this bike on several other steep climbs since this video and so far I haven't had to use the lowest gear.
http://www.youtube.com/watch?v=5UoYR4Awhfk
http://www.youtube.com/watch?v=5UoYR4Awhfk
I've been on hills like that when I thought if I only steered into that oncoming car the pain would be over faster. lol
AzTallRider
04-20-11, 12:54 PM
I switched from compact to standard (53/39) a few months ago, and like it a lot better for here in Arizona. Cassette is 12-27, and I am (almost) never in the 27. The big test for me will be the San Diego Century (http://ridewithgps.com/routes/75323) on May 21. 8,700' of climbing, with some pretty steep sections. It's not a race, so I just have to be able to get up without walking.
For short sections like the ones you noted, sometimes you just have to stand up and gut it out. I could tell that is what you did in the video so really that's what it takes. Sometimes I'll just stay seated and lean over the bars in a low position and try to stay as smooth in the pedal circle as possible. Either way 13% is gonna hurt. The more often you do really steep sections the better you'll get at them. As a side benefit, the 6% stuff will seem a lot easier too.
I do stand in the steep sections. I can't do that for long, and my cadence better be low, or I'll flood myself with lactic acid and just die.
I have found my running training (for triathlon) has been very helpful to climbing, especially standing. Most of the same muscles are being used, I would guess. Not withstanding, I still suck at climbing!
freighttraininguphill
04-20-11, 01:12 PM
I've been on hills like that when I thought if I only steered into that oncoming car the pain would be over faster. lol
:lol:
You know what's odd? That hill didn't hurt too much, just lots of effort. However, the next hill hurt like hell, and it wasn't even as steep! This kind of stuff happens all the time. I'll climb a 15% grade that doesn't hurt or barely hurts, then I'll climb a 10% grade that hurts more. Weird. Maybe it's because the 10% grade happens after a descent, therefore my legs cool off and it's like climbing without being warmed up.
AzTallRider
04-20-11, 01:13 PM
I do stand in the steep sections. I can't do that for long, and my cadence better be low, or I'll flood myself with lactic acid and just die.
So, what do you do when you can't do something for as long as you want/need to? You do a lot more of it! Going OTS is like anything else, you just need to train it up. Set time goals for how many seconds you stay standing, and gradually increase them, while working on being smooth and relaxed. You'll get there.
freighttraininguphill
04-20-11, 01:13 PM
Not withstanding, I still suck at climbing!
Not as much as me:p I just watched your video and compared it to mine. We're both climbing 13% grades, but you're climbing them faster than me.
Not as much as me:p I just watched your video and compared it to mine. We're both climbing 13% grades, but you're climbing them faster than me.
Ummm...I doubt that! I passed only three people on a climb at Tierra Bella last weekend, and they were pushing their bikes uphill as they walked...
;~)
I just asked in your other post, if you were riding the Look and I see you are. I don't know what grade I was climbing here, but I had my heart rate pegged at my max which is 170. I did pick up a lot of strength riding in big winds here. I don't know if it's as windy out there.
jimmuller
04-20-11, 01:53 PM
Sarals, you got a lot of answers and some are even helpful. But some fundamental perspective might help. Then you can implement the solution however your budget and existing components allow. It isn't complicated...
Barrettscv hit it close with his gear chart. In the old days they used to compute gear number as the equivalent wheel diameter you would have if your cranks were connected directly to the pedals like a highwheeler. Doing that calculation is easy. Divide your chainring tooth count by the rear cog tooth count. Since you are interested in the low gear, use 34 / 25. Then multiply that by the diameter of the rear wheel. For the accuracy required here you can just use 27". That gives you a low of about 36.7 "gear-inches", or just 37 inches.
Now for the perspective part. In the old days, i.e. the 70's bike boom, a general-use 10-speed (i.e. 2x5) sport bike came with a gear range of 38 to 100. Anyone who bought a new bike back then and did their first riding discoverd that 38 was good enough for minor hills but not for real ones. Your 36.7 isn't really lower enough to be different.
However a gear closer to, say, 30 will feel much easier. That's 18% lower than yours. You can get a gear like that any way you wish. My two bikes use 34/28 (for 32.8 inches) and 36/30 (for 32.4 inches). Any combination of this large a chainring and this small a cog will do, as long as your derailleurs can handle it.
Sarals, you got a lot of answers and some are even helpful. But some fundamental perspective might help. Then you can implement the solution however your budget and existing components allow. It isn't complicated...
Barrettscv hit it close with his gear chart. In the old days they used to compute gear number as the equivalent wheel diameter you would have if your cranks were connected directly to the pedals like a highwheeler. Doing that calculation is easy. Divide your chainring tooth count by the rear cog tooth count. Since you are interested in the low gear, use 34 / 25. Then multiply that by the diameter of the rear wheel. For the accuracy required here you can just use 27". That gives you a low of about 36.7 "gear-inches", or just 37 inches.
Now for the perspective part. In the old days, i.e. the 70's bike boom, a general-use 10-speed (i.e. 2x5) sport bike came with a gear range of 38 to 100. Anyone who bought a new bike back then and did their first riding discoverd that 38 was good enough for minor hills but not for real ones. Your 36.7 isn't really lower enough to be different.
However a gear closer to, say, 30 will feel much easier. That's 18% lower than yours. You can get a gear like that any way you wish. My two bikes use 34/28 (for 32.8 inches) and 36/30 (for 32.4 inches). Any combination of this large a chainring and this small a cog will do, as long as your derailleurs can handle it.
Thank you, Jim!
Actually, you anticipated my next question - my rear derailleur. Reading up on the Shimano Ultegra 6700 12-28t cassette, it says "Shimano RD-6700 rear derailleur required". Yeup, do I have an RD-6700? I don't know! It is Ultegra gruppo on my Look, but it seems that's not completely true, because the cassette is apparently a 105. How do I find out?
Thanks again!
That's the very one.
It is short, oh, 3 miles, but there are two kicks in it. The first one is about 100 yards long at 13% or more, and the last one is near the top, with a left curve in it, and it's about a quarter mile long. It's 13% or more, too.
I'm a glutton for pain, and I usually climb it at least once a week! I just want some more HELP from the bike!!!! Cat *anything* racer I'm not, and I'm on the 50+ thread because???? - ;~)
A quarter mile finish with 13% grades is a tough climb for most riders!
With a 34-25 and a 13% grade, I'd be standing and balancing the bike below 4 mph, using my weight on the downstroke. That's a cadence between 35 and 40 rpm. (30 rpm is just one pedal stroke a second). I've been as low as 29 rpm, 2.7 mph on some climbs here. If I tried to maintain the cadence I was using while sitting, my heart rate would max out.
On longer climbs, I'll keep an eye on my heart rate monitor, so I don't go so hard that I blow up before the top of the climb.
I'd much rather have a 12-27 instead of an 11-28. I would rarely need the 50-11 top gear, only on downhills over 35 mph. The 12-27 keeps the 16 cog, which cuts the big jump from 15 to 17 in half.
At 90 rpm, the 50 chainring and 17,16,15 cogs is 20.6 mph, 21.9 mph, and 23.4 mph.
At 90 rpm, the 34 chainring and 17,16,15 cogs is 14.0 mph, 14.9 mph, and 15.9 mph.
On your setup, I think the largest you can go is a 27. Any bigger you'll have to change the derailluer.
Barrettscv
04-20-11, 02:11 PM
Thank you, Jim!
Actually, you anticipated my next question - my rear derailleur. Reading up on the Shimano Ultegra 6700 12-28t cassette, it says "Shimano RD-6700 rear derailleur required". Yeup, do I have an RD-6700? I don't know! It is Ultegra gruppo on my Look, but it seems that's not completely true, because the cassette is apparently a 105. How do I find out?
Thanks again!
Hi Sarals,
If the plan is to use a 12-28 cassette, any Ultegra Derailleur will work. The 2010/2011 6700 is rated for 28, but will take a 30 or even a 32 cog, depending on the length of the hanger that it is attached to. The older 6600 is rated for 27, but a 28 will fit no matter how long the bike hanger.
Michael
freighttraininguphill
04-20-11, 02:19 PM
Ummm...I doubt that! I passed only three people on a climb at Tierra Bella last weekend, and they were pushing their bikes uphill as they walked...
;~)
OK, OK, it's probably the helmet cam vs. my handlebar-mounted cam then:p I have noticed that helmet cam videos look faster than handlebar cam ones:p:D
Speaking of gears, I put the same setup on my road bike last summer and it rocks! The bike is a 2011 Specialized Dolce Triple that came with a 13-26 cassette and a 30-tooth small chainring. After a sufferfest of a climb up Donner Pass Road, I replaced the cassette with a Shimano MegaRange 11-34 and the small chainring with a 24 (see, I told you I suck at climbing:p). After doing all that I had to replace the rear derailleur with a Shimano Deore long-cage mtb derailleur.
That Sirrus hybrid I rode in my video I bought used and it only had a 24-tooth largest rear cog and a 28-tooth small chainring. The 11-34 cassette/24-tooth chainring combo is the lowest gearing possible on both bikes.
Well, thanks fellas. I'm going to go ahead and order a 11-28t cassette. I have a new set of (used, but nice) Easton EA90 Aero wheels that I'll put the cassette on, and then swap with the Fulcrum 7's already on the bike. Every little bit should help!
Done - Shimano Ultegra 6700 11-28t cassette on the way to me...
AzTallRider
04-20-11, 04:28 PM
Done - Shimano Ultegra 6700 11-28t cassette on the way to me...
Don't forget the tools needed to install it!
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